The Fixation of Radioiodine with Portland Cement. Part II: Radiation Stability Tests

Barium iodate, which is used as the vehicle for storing ¹²⁹I in Portland cement concrete, is subject to radiolytic reduction to iodide. This could result in an increase in the leach rate of¹²⁹I during storage due to the reduction of insoluble iodate to soluble iodide. The measured G value (ions of I^- per 100 eV or per 1.602 × 10^-17 J) was found to be 0.083 for concrete containing 9.05 wt% iodine. The reduction resulting from internal irradiation alone is quite small; only ∼0.21% of the stored ¹²⁹I would be reduced in 1000 yr.